At least two research firms upped their Google price targets to $1,000 Thursday morning, just two days after the Internet company’s share price topped $800 for the first time ever. Sanford C. Bernstein cited the emergence of mobile as a significant growth driver and YouTube, which it deems as an “underappreciated asset” as the main catalysts behind its decision to lift its price target to $1,000 from $820.

“We believe mobility, together with continued innovation in search such as new formats and better targeting, will support growth of search revenues in the double digits for several years to come,” Berstein analyst Carlos Kirjner wrote to clients. “We also believe YouTube is already a multibillion dollar business, growing fast and with healthy operating margins, whose growth potential is not fully reflected in consensus.”

Kirjner said the risks to his call are aggressive investments in research and development that don’t pay off, antitrust regulation and Google’s ability to continue improving the return on investment on its big money maker — search.

“The fundamental question (and risk) Google investors face is whether Google can continue to improve search and search advertising ROI so that it can outcompete other media and marketing tools for the incremental advertiser dollar,” Kirjner says. “We think these risks are real and well worth taking given the potential upside.”

Shares recently edged up 0.7% to $797.83. The stock, which traded as high as $808.97 on Tuesday, is up 30% throughout the last 12 months. Only three other companies are currently in the $800 club: Berkshire Hathaway’s Class A shares, Seaboard Corp. and NVR Inc. Even Apple Inc. couldn’t make the club; it briefly topped $700 in mid-September before turning sharply lower.

Bernstein and CLSA appear to be the first two firms to slap $1,000 price targets on Google, according to data compiled by FactSet. As the chart shows below, FactSet estimates the current average price target on Google is $844.83.

FactSet

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